1. Field of the Invention
The present invention relates to a machine tool control apparatus which measures not only the position/speed of a driven body but also the acceleration thereof and which performs control by taking account of the acceleration.
2. Description of the Related Art
In a machine tool control apparatus, feedback control is performed by detecting the position/speed of a driven body and by computing the amount of control based on the difference between the detected position/speed and its command value. However, if a low-rigidity part such as a joint is interposed between the driven body and the detector, as is the case when the driven body is, for example, an indexing table, the driven body may vibrate due to the presence of the low-rigidity part. To address this problem, there is a need to perform control by detecting the acceleration of the driven body and compensating the command value based, for example, on the detected acceleration.
When installing an acceleration sensor for detecting the acceleration of the driven body, the sensor must be mounted by orienting the acceleration detection element so that its detection direction coincides with the direction in which the acceleration is to be detected; otherwise, an error would be induced in the detected acceleration, and the desired controlled condition could not be achieved.